Piston



A. M. FRANCHI PISTON Filed Jan. 18, 1923 fi MIMI Ill I I v I INVENTORillfllnlm I fimba ATTORNEY Patented Nov. 2d, 1923.

nano is. ransom, or new roan, n. Y., nssren'oa ro ama es: nrnennssrrsron conronnrron, or new roan, n. Y., A conronn'rron or new roan".

PISTON.

Application filed l'anuary 18, 1923. Serial Etc. 613,388.

To all whom it may concern Be it known that 1', Anne M. l nnnom, acitizen of the UnitedStates, and resident of the city of New York, iiithe county of New York and State of New York, have invented certain newand useful. Improvements in Pistons, of which the following is aspecification.

The present invention relates to improvements in pistons, and moreparticularly to trunkpistons, especially designed for use with internalcombustiorr engines.

The inain object of the invention isto provide a simple, inexpensive anddurable piston rod connection, wherein wearing of the elements iscompensated, lost motion of the piston being thus precluded.

With these and other objects in View, which will more fully appear asthe nature of the invention is betterunderstood, the same consists inthe combination, arrangement and construction of parts hereinafterdescribed; pointed out in the appended claims and illustrated in theaccompanying drawings, it being understood that many changes may be madein the size and proportion of theseveral parts and details ofconstruction within thescope of the appended claims, without departingfrom the spirit or sacrificing any of the advantages of the invention.

Une of the many possible embodiments I of the invention is illustratedin the accompanying drawings, in which Figure 1 is a central verticalsection taken vthrough a piston constructed in accordance with thepresent invention; Fig. 2 is atop plan view of one of the elements ofthe piston rod connecting. means; Fig.3 is a front elevation oi the saidelement; and Fig. i is atop plan view of a spring element co-operzaingwith the element shownin Figs. 2 an 3.

In the drawings, the numeral 10 indicates a trunk piston, includingacylindrical shell lil which is open at one of its ends and closed atits oppositeend by a head 12.

From this head extends centrally downwards into the shell a-hollow boss13, strengthened by ribs 15 and provided with reduced cylindricalenteriorly screw threaded lower portion 16. threads of this portion meshthe interior threads of a sleeve 17, which is provided upon its freelower end withan inwardly 24 is split to allow of extending annularshoulder 18. In the boss 13 is formed, above its screw-threaded por-'tion', an interior annular shoulder 19, against which abuts a bearingcup 20, with which co-operates a ring-shaped bearing member 21. llhecupand this hearing member constitute a spherical socket into which isfitted the spherical head 22 of a piston rod 23. The bearing member 21is shiftably mounted in the sleeve 17, it being substantiallywedgeshaped, its underface extending in a plane at an angle to thelongitudinal axis of the piston shell. With this wedge-shaped hearingmember co-operates a split ring 24, which rests upon the annularshoulder-18 of the sleeve 17. it being adapted to slide on the saidshoulder laterally. This split ring is also wedge-shaped, its upper facebearing against the lower face of the bearing member21 throughout itsentire area. From the foregoing and from an inspection of Fig. 1 of thedrawings it. appears that the bearingl member 21 and the split ring 24taper in opposite directions; whereby, when the split ring 24!: isshifted laterally in the direction of the arrow shown in Fig. 1

of the drawings, the bearingmember 21 is in contact with the underfaceof the bearingv member 21, there is a spring 25 provided.

This spring is made in the form of an open ring, encircling the sleeve17. One of the ends of this ring, denoted by thenumeral 2'6,is bentinwards toward the center of the ring and extends through a slot 27. inthe sleeve 17 into a recess2'8 in the split ring 24:. This recess isformed in the thickest portion of the split ring, as clearly appearsfrom 1F igs. l and 3. of the drawings. The ring a proper assembling ofthe elements. I

The upper end of the sleeve 1? is pro videdwith a flaring skirt 29, inwhich oil collects as the piston is operated in its cylfinder. Theoilflows from this skirt through the re istering apertures 30and 31 in there duced portion. 16 of-fthe boss 13 and the bearing cup 20,respectively, and through a bore 32 in the said bearing cup to the Withthe spherical head 22 of the piston rod, whereby proper lubrication ofthe bearing cup,

bearing member21 spherical head 22 of the piston rod 15 obtained.

the piston, to compensate for the wear.

Lost motion of the elements is thus pre-' vented. It is to be noted thatthe spring at the same timepreventsturning of the bearing member 21.

What I claim is r x 1. The combination with a trunk piston having a bossprojecting downwards from its head into its shell provided with acylindrical portion having exterior screw-threads, of a sleeve havinginterior screw-threads meshing with thoseof said cylindrical portionprovided at its free end with an annular inwardly projecting shoulder,aspherical socket comprising a stationary member within said cylindricalportion anda movable member Within said sleeve, a piston rod projectinginto said sleeve having a spherical head seated in said socket, themovablemember of said socket being Wedge-shaped and shiftable Withinsaid sleeve in the direction of the longitudinal axis of saidpistonshell, a wedge-shaped ring shittable latorally on said shoulder andabutting against said-movable socket member, said sleeve being providedwith a slot in alignment with I a recess in said ring, and a ring-shapedspring surrounding said sleeve having spaced apart ends, one of saidends being bent radially inwards and extending through said slot intosaid recess to shift said ring laterally so as to cause movement of saidmovable socket member in the direction of the longitudinal axis of'saidsleeve, whereby Wear of said socket members and the spherical headwithin said sleeve and abutting against said movable socket member, anda ring-shaped spring surrounding said sleeve having spaced apart ends,one of said ends being bent radially inwards and extending through saidsleeve into engagement. with said laterally movablemember to shift thelatter laterally so as to cause movement of said movable socket memberin the direction of the longitudinal 'axis of said sleeve.

Si ned at New York, in the county of New ork and State of New York, this18th day of October, A. D. 1922.

ALDO iu. FRANoHi.

